This application claims the priority of German patent document 10 2004 004 387.6, filed Jan. 29, 2004 (PCT International Application No. 01.29.2004), the disclosure of which is expressly incorporated by reference herein.
The invention relates to a vehicle seat.
German patent document DE 100 61 027 A1 discloses a vehicle seat for a convertible or a roadster, in which an electric heating device and a blower are combined in a housing to form a single component that is arranged underneath the horizontal net of a windbreak which is mounted in the vehicle and is composed of a horizontal and a vertical net. Air that is sucked in by the blower is heated by the electric heating device and fed via a connecting hose to an air vent arranged between the upper side of the backrest and the underside of the head cushion of the headrest. The warm air is blown out of the air vent directly into the nape and head area of the seat occupant, so that warm air is supplied to this area even when the vehicle is traveling at high speed. The air vent contains two sets of pivotable louvers which are arranged one behind the other in the direction of air flow, one set being pivotable about a horizontal axis and the other being pivotable about a vertical axis, so that the direction of air outflow out of the air vent can be set.
In a vehicle seat disclosed in German patent document DE 101 60 799 A1, in particular for open motor vehicles, the device for heating the nape and head area of the seat occupant has a warm air blower which is arranged at the rear side of the head cushion and whose pressure connector ends in the intermediate space between the head cushion of the headrest and the upper side of the backrest. The pressure connector has a vent opening which is directed onto the nape and head area of the seat occupant. Line connectors which end with a vertically extending line section that has venting openings are connected to the side of the pressure connector. The line sections are connected to the line connector by means of a rotary bearing so that the venting direction of the warm air can be changed easily by rotating the line sections, and can be set, for example, to the shoulder area of the seat occupant.
German patent document DE 196 54 730 C1, FIG. 3 discloses a vehicle seat with an integrated headrest, in particular for a vehicle which is to be driven in an open state. A blower and a heat exchanger via, which heats the air that is sucked in by the blower, are arranged behind the rear wall of the passenger compartment. A plurality of nozzles, whose nozzle stems which end at the rear of the backrest and are connected to an air line leading to the heat exchanger and blower, are arranged spaced apart from one another in the horizontal direction in the nape area of the backrest. The air which is sucked in by the blower is heated in the heat exchanger and fed via the air line to the nozzles where it is blown out into the nape and head area of the seat occupant.
One object of the present invention is to provide a vehicle seat of the type described above with a small-volume device which can be integrated satisfactorily for heating the nape and head area of the seat occupant with warm air.
Another object of the invention is to provide such a device which is efficient and which does not disrupt the esthetics of the vehicle seat and of the passenger compartment.
These and other objects and advantages are achieved by the vehicle seat according to the invention, which has the advantage that all of the necessary components for generating warm air are contained in the air vent which is located in the intermediate space between the backrest and head cushion of the headrest. Efficient conversion of energy is ensured by the direct electrical heating of the air which passes through the air vent. In order to apply warm air to the nape and head area of the seat occupant it is generally sufficient to provide just the electric heating unit, which is preferably an electric heating coil, in the air vent, because of the back flow of air which is always present and which occurs to a greater degree when a vehicle is driven with an open passenger compartment. As a result of this back flow, a sufficient quantity of air always passes through the air vent and is heated by the heating unit. In addition, according to one advantageous embodiment of the invention it is possible to integrate a blower into the air vent, which blower is preferably embodied as a miniature fan. With this structural configuration of the air vent it is advantageously possible to use known hairdryer technology.
In addition to the fact that the heating device which is reduced to the air vent is inconspicuously installed in the vehicle seat, additional air ducts in or behind the backrest and additional assemblies for the blower and heating unit in or behind the backrest are dispensed with. By eliminating additional components in the backrest the seating pressure comfort is improved and the upholstery of the backrest can be made simpler.
According to an advantageous embodiment of the invention, the air vent is arranged on the supporting bracket of the headrest or on the underside of the head cushion. This arrangement allows the heating device for the nape and head area of the seat occupant to be retrofitted, and permits the device to be provided as an accessory which is not specific to the vehicle or manufacturer. If the vehicle has a rollover bar that is assigned to the vehicle seat, the air vent can also be attached to the rollover bar as a retrofittable accessory.
According to another advantageous embodiment, the air vent is provided with a panel which covers the remaining intermediate space between the backrest and head cushion and preferably engages over both the rear of the backrest and the rear of the head cushion. As a result, cold air flows which pass by the air vent into the nape and head area of the seat occupant are screened off.
According to still another advantageous embodiment of the invention, the air vent is pivotable about a vertical and/or horizontal pivot axis, making it possible to vary the outflow direction of the warm air stream.
The air vent can be pivoted about three orthogonal axes if the housing of the air vent is of spherical design and is accommodated in a displaceable fashion in two spatially secured spherical shells. The spherical shells can be attached to the supporting bracket or, when there is a backrest with an integrated headrest, they can be attached in the backrest itself.
The vehicle seat according to the invention may be a driver's seat, passenger's seat or a rear seat or rear bench seat. In the latter case, each seating place on the rear bench seat is assigned a heating device for the nape and head area of a seat occupant occupying the seating place.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.